Laser Cavity and Amplification Principles

This lecture covers the principles of laser cavities, including the use of stimulated emission, active medium, mirrors, and feedback effects to amplify light and create coherent radiation. It also discusses the characteristics of perfect and real mirrors in Fabry-Perot cavities, the impact of finesse on intensity, and the transverse modes. Additionally, it explores the quality factor of optical cavities and the amplification process in lasers, focusing on the role of inversion of population, absorption, and stimulated emission. The lecture concludes with the ideal and real amplifiers and the creation of narrow emission spectra in laser cavities.